# Author::    Nicolas Pouillard  <ertai@lrde.epita.fr>.
# Copyright:: Copyright (c) 2004, 2005 Uttk team. All rights reserved.
# License::   LGPL
# Revision::  $Id: /w/fey/uttk/trunk/lib/uttk/strategies/Block.rb 22117 2006-02-22T08:56:22.146625Z pouillar  $


module Uttk

  module Strategies

    # I can evaluate a Ruby block. The test fails if block raise an
    # excption or return a false/nil value.
    class Block < IOBased
      include Concrete


      def self.create ( *a, &block )
        raise ArgumentError, 'need a block' if block.nil?
        strategy = new(*a)
        strategy.test = block
        strategy
      end


      def test=(block1=nil, &block2)
        if block2
          @test = block2
        elsif not block1.nil?
          @test = block1
        else
          raise ArgumentError, 'no block given'
        end
      end


      def prologue
        super

        if @test.is_a?(String)
          str = @test.dup
          @test = lambda { eval str.do_symtbl_gsub(@symtbl) }
        end

        @result, @raised_exception = nil, nil
      end
      protected :prologue


      def run_impl
        begin
          @result = @test[*@args]
        rescue Status => ex
          raise ex
        rescue Exception => ex
          @raised_exception = ex
        end
      end
      protected :run_impl


      def assertion
        fail @raised_exception if @raised_exception
        pass if @result
        fail @result
      end
      protected :assertion


      attribute :test, 'a Proc to call with args', :mandatory, :invisible
      attribute :args, 'arguments for the `test\' proc', []

    end # closs Block

  end # module Strategies

end # module Uttk

#FIXME: adapt me to a real unit test suite
# if defined? TEST_MODE or __FILE__ == $0

#   include Uttk
#   include Strategies

#   $x = 0
#   suite = Suite.new
#   suite.strategyclass = Block
#   suite.name = 'Test the Block strategy'
#   suite.symtbl = SymTbl.new
#   suite.symtbl[:loader] = Loaders::Yaml.new

#   t1 = Block.create { $x = $x.succ }
#   t1.name = 'test 1'
#   suite.create t1

#   t2 = suite.create
#   t2.name = 'test 2'
#   t2.test = proc { $x = $x.succ }

#   t3 = suite.create
#   t3.name = 'test 3'
#   t3.test = '$x = $x.succ'

#   t4 = suite.create(Block.create { $x == 3 || fail("x != 3 (with x == #$x)") })
#   t4.name = 'test 4 PASS'

#   t5 = suite.create(Block.create { fail("x != 3 (with x == #$x)") })
#   t5.name = 'test 5 FAIL'
#   t5.weight = -1

#   log = Logger.new(Dumpers::Yaml.new(STDOUT))
#   suite.run(log)

# end